Skarmory isn't an absolute counter of Tornadus, and for instance his Therian forme, in rain-less teams because some Tornadus carry Heat Wave. So, it should be stood out that this sets should not be used in a weather team if it isn't rain.
About Forretress, HP Ice is very useful, true, I was surprised the other day when I was using a Gliscor against a Forry thinking it would be a free Substitute and it used HP Ice causing a great damage.
A question about the set, why carrying a -Spd nature instead of -At nature?
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